Homokinetic joint



Oct. 21, 1952 4 G. L. A. DEVOS 2,614,404

' HOMOKINETIC JOINT Filed Oct. 5, 1948 8'Sheets-Sheet 2 Gaston LowsARTHUR DEvos \N vEnn-oi m'rolanerg Oct. Z1, 1952 G. A. DEVOS AHOMOKINETIC JOINT 8 SheetsSheet 5 Filed 001;. 5, 1948 GASTON Lows Ran-maDeuos Oct. 21, 1952 I v s 2,614,404

HQMOKINETIC JOINT 8 Sheets-Sheet 4 Filed Oct. 5, 1948 G. L. A. DEVOSHOMOKINETIC JOINT 'Oct. 21, 1952 8 Sheets-Sheet 5 Filed Oct. 5, 1948Oct. 21, 1952 e. A. DEVOS HOMOKINETIC JOINT 8 Sheets-Sheet 6 6m mm 89LEm. 8 E

Filed Oct. 5, 1948 Oct. 1952 G. L. A. DEVOS HOMOKINETIC JOINT 8Sheets-Sheet 7 Filed Oct. 5, 1948 665111! Lquus Atrvwn. OB

(Vano8,

Oct. 21, 1952 G. A. DEVOS HOMOKINETIC JOINT 8 Sheets-Sheet 8 Gag-nu LHum) De as mvrmqm QTTDPIYEYS Filed Oct. 5. 1948 Patented Oct. 21, 1952:AppIicationOctober 5, 1948, Serial No. 52,885 In France January "19,1948 g .4 rGlaims.

The present invention relates itorimprovements in transmission jointsz-for ashaits 1ofwariable1neiative angular position, and .cenableszxperfectly homokinetic joints :to. be :obtained'in whichitthtransmission is effected smoothly without jerks by means of apluralityof setswofzmembers; the symmetry of which :withfirespect to .the medial.axis of the joint is always:constantlysretained.

' A joint according to the present iinventionvessentially comprises'twosegments,.:each of which is adapted to rotate in azgrooveof a*jawxsupported by the end of the.correspondingxshaft, said .two segmentsbeing :coupled .itotone another by a. pivot which is constantlyretainedaalong the 'bisector of the angle -formed:by;the:two shafts,:bymeans of a guide member which :is adapted to slide-on said pivot andwithawhichzare :e gaged driving pins which are at right angles :-;to'the pivot and which are respectively: supported by each of the jaws, inboresof which. they'd-are adapted to pivot.

Other features of the invention, ease-well :as certain-modifications ofconstruction'will become apparent from the ensuingv description :whichismade with reference .to :the accompanying .dia-

- grammatic drawings in which:

. S'Figf. 1 is an elevational view :withrpants -in sec- ;ti'n.of a jointaccording to .a :first.;embodiment, the two imovable :shafts ibein zocat diin al e zment-with, one another. V .1

, Fig. 2 a..-simi1ar view, the imovable,- shafts being. arranged "at,-ani..anglexto one another.

- Figs.. 3 and tare perspective views of thissa'me joint inthe twocorresponding positions;

*Fig. 5 showsone of the jawsgpartly iniSBQtiOII;

Fi shows t is s me i wia tersit has been o- .tated a quarter of arevolution;

Fig. 7 is an end view of said j aw in ;the :whichit occupiesin Fig. 5 s

Fig. 8 .shows..=a "longitudinally. slotted movable position shaft;

, Fig. 9isa sectional view of said shaft along .the line AB of Fig.8;

,Figs. 10 and 11 show anelevational-andaplan view of a femalesegment1and;Fig.,.12.a plan view of a male segment;

' Figs. 13 and 14 show respectively a trontzand a 1:2.SEE-22155110117815? c ws hreaided co lar; i-Eigs 2.to.125 show amodification ofconstruc- 15 2 9 1 of th n tud na slot o the movable-shaft ;Eigs...26.-=and Show a modification .of the -p v t;

1Eig. 2,8 .showstthe collar. correspondingto this mod fic t on;

..F!ig. 29.show,s amodifieationofZthe.coupling of .the casing caps,providing an automatic take-up o t lay andithej ock n .otthe .pivot inthe axial di ection;

axial lockin'gdevic 'forthe. p v t;

F s 4 and-3 s a ,c odific t o of sonstr ction of th .e upl n segments.

Eig.t3fi show a segmentedgspring;

:Figs. 3.7 and '38 respectively show elevational andplan views. of ;amodificatio-n of the guide 1 member;

E Fig.-39 shows an 'elevationa'l view,; partly'in-section, of anotherembodiment of the joint "accordingto the invention, the -movable shafts"being-in alignment with one another.

FigJIO is a similar view, with the *movable shafts arrangedat an angleto one another;

Fig.-41 s'howsthe assembly of the -transmiss'ionmerhbersofsaid joint;

"Figs. :42 to-s47are detail-views 0f the .various membersof said joint.

" In the joint illustrated in Figs. 1 to7'21 ,".='the -two=movable:shafits terminate :in t-wozsymmetrical :jaws TI, 12. In-.agroove of :the jaw l a female segment 3 sis. adapted to slide sin-adiametrical plane, while in ia-. similar.grooveofxthe ijaw"2 (Figs. :1,5 and 7 .-;a'.malesegment J4 -:is adapted :to slide :under the rsame:conditions. -.These two their housing: ;by the .Jbacks lo'f ithe:drivingi pins segments Fi-gs. 1 .and:10:- to v'12.) are aretained -;in

6'! (Figs. :1. .and 31:5) tandiare :coupled sto ,one

geometrical prcentre act the. joint .and constantly..=.coincides-withthevbisector .of :the angle .sub- 'TGGHdGdZbBtWBBII:Tthegeometrical axes :oftheztwo :sha'tts; to ibegooupled. Thisretention :of athegcoincidencewbetween saidibisec.tor and said; pivot-is-=:ensured byoaguide member :8 .CEigs. ;1, 416 and 177;) which .;ismountedzloose:onsaidvpivotan'd .in

anannular groove. 8.,a'gofzwhichaare engaged-2pm- ;jecti-ons .of thedriving spins :fi-el .which are adapted :EtoxDivOt: iinn-iradial-sbores.of the correthat each of its ends is provided with a projection aengaged in a groove 9a of a collar 9 (Figs. 1 and 21) on which screw thetwo halfcaps lill I of the casing (Figs. 1 and 20). Relay caps 12-13(Figs. 1, 18 and 19) are inserted between these casing caps and the jawsl2.

In order to preventviolent jerks during power transmission, a torsionalelasticity is imparted to the two shafts by providing them'withlongitudinal slots as shown at 2?) (Figs. 8 and 9). This arrangementenables the size of the jaws to be decreased without danger of theirbreaking. This arrangement can moveover be usefully applied to otherpurposes; it may in particular be applied to torsion bars.

The joint which has just been described operates under the followingconditions:

When the two shafts are in alignment with one another (Fig. 1), thewhole joint rotates as an integral unit without any relative movement ofits various parts. On the other hand, if the two shafts are arranged atan angle to one another (Fig. 2), the segments 3& swing about the pivotand slide in the jaws i-2; the driving pins in turn slide axially in theguide member 8 and pivot in the bores of the jaws l-2; the guide member3 engages further over the driving pins 51 and slides on the pivot 5.Therelay caps l2--l 3 move between the jaws l-2 and the casing caps Iil-I 1, their travel being limited by the collar 9 and the shoulder of thejaws l-Z which are provided with recesses as shown at 2a. The casingIll-ll remains centred on the bisector of the joint by means of thecollar 9 and the pivot 5.

It is very easy to assemble the members of this joint. The segments 34are inserted in their respective jaws l2 and are retained therein byplacing the driving pins 6-4 in position in their respective bores. Thepivot 5 is then inserted in the bores of the segments 3-4, which arethus coupled together, and in the bore of the guide member which is thuscentred. The collar 9 is then placed in position, by slightly ovalizingit, thereby increasing the diameter thereof. The projections 5a are thenpositioned in the grooves 9a by snapping the collar 9 in place on theshoulders of the pivot 5. The relay caps I2l3 are placed on the jaws l2and finally the casing caps Ill-H are screwed on the collar'El, on theflanks of which are inserted foil Washers or gaskets such as M (Figs. 30and 31) which enable play to be taken up in case of wear. Notches 10a(Fig. 3) are provided for screwing the casing caps Ill-ll which arelocked by punching the portions facing the recesses I la.

Figs. 22 to 25 show modifications of construction of the longitudinalslots provided in the two movable shafts to be coupled. The slots 21)may be provided symmetrically or not in different places and the numberthereof may vary.

In the modification shown in Figs. 26 to 28, the ends of the pivot 5 areprovided with two shoulders 5a which straddle the collar 9 which isprovided with recesses 9a to accommodate them.

According to another modification shown in Fig. 29 one of the ends orboth of the ends of the pivot 5 are provided with a bore in which ishoused a locking piston It provided with shoulders of complemental shapeto the circular grooves 101) provided in the casing caps 1-! l. The capsare thus coupled to one another and, by giving to said grooves afrusto-conical crosssection, an automatic take-up of the play isobtained by the action of the spring [1. A felt 4 washer l9 providesfluid-tightness between the caps Ill-4|.

In Figs. 32 and 33 another modification has been shown according towhich the locking of the pivot 5 in the axial direction is obtained bymeans of recessed washers l5 housed in circular grooves 5b of said pivotand interposed between the coupling segments 3-4. The chamfer with whichthey are provided is turned over in slots provided in one of saidsegments to which they are thus locked.

In the modification shown in Figs. 34 and 36, the locking of the pivot 5in the axial direction is obtained by means of segmented springs l8engaged in circular grooves 3a provided in the bores of the femalesegment 3. Cylindrical plates of the same diameter as the bores may beinterposed between the segmented springs IS and the ends of the pivot 5.

In the arrangement of Figs. 34 and 35, the segments 3 and 4 are providedwith semi-circular shoulders 3b which retain themin the jaws, thegrooves of which are inthis case shaped accordingly.

Again, according to this same modification of Figs. 34 and 35, thesegments 3-4 are provided with a dorsal rib 3a which increases theirstrength and their area of contact with the jaws, the grooves of whichare provided with a housing to accommodate said rib.

Finally, in the modification of Figs. 37 to 47, play take up rollers20'with compression springs 2| are arranged inside the jaws I-2. Theguide member is formed by a bush 8 secured to a disc 8a which isoverlapped by the projections of the driving pins 6l instead ofoverlapping them as in the previous embodiments. The pins 6-'! areadapted to pivot in bushes 23-24 of complemental shape to the outside ofthe jaws and pinned in same. Similarly, the pivot 5 is providedwithbushes 25-26 which are forcibly engaged thereon. The pivot 5 islocked in the axial direction, by means of recessed plates 22 (Fig. 43)which are inserted by meansof a bayonet fitting in recessed circulargrooves 3e of the segment 3 (Fig. 42) and locked by punching the end ofthe recesses of said grooves. The jaws are provided with reinforcingshoulders 20 (Fig. 40) against which the relay caps l2l3 are adapted toabut.

homokinetic joint is obtained which has a multiple drive. I-Iomokineityis obtained owing to the symmetry of position of the symmetrical memberslocated on either side of the medial axis of the joint and to thesynchronism of their movements. The multiple drive is obtained by meansof the combination of the coupling segments and the driving pins. Theperpendicular position of said segments relatively to that of said pinsfurthermore ensures constant smoothness in the transmission of power.Furthermore, the central pivot forms a complementary transmission memberbetween the driving segments which it couples and the driving pins whichguide it by means of the guide member.

I claim:

1. A homokinetic joint for shafts of variable relative angular positionwhich comprises a jaw secured to the coupling end of each shaft, eachjaw having a groove-and a bore therein, a segment mounted on each jawand rotating in said groove, a pivot coupling said segments to oneanother, a guide member retaining said pivot constantly on the bisectorof the angle formed between the two shafts and sliding on said pivot,

Thus, according to the invention, a perfectly a pair of half capsforming a casing, a collar on which the half caps are engaged, saidcollar positioned on said pivot; a driving pin pivotally mounted in thebore of each jaw at right angles to said pivot, and operatively engagingsaid mem" her, said guide member comprising a disc slidably mounted onthe pivot of the segments and a circular groove provided in the discengaging projections carried by each driving pin.

2. A homokinetic joint for shafts of variable relative angular position,which comprises a jaw secured to the coupling end of each shaft, eachjaw having a groove, and a bore therein, a segment mounted on each jawand rotating in said groove, a pivot coupling said segments to oneanother, a guide member retaining said pivot constantly on the bisectorof the angle formed between the two shafts and sliding on said pivot, adriving pin pivotally mounted in the bore of each jaw at right angles tosaid pivot and operatively engaging said guide member, tenons providedon the ends of the pivot, a grooved collar engaging said tenons, a pairof half caps forming a casing, said casing centered on the axis of thejoint, said half caps secured on the collar, and a relay cap insertedbetween each of the jaws and the corresponding casing cap.

3. A homokinetic'joint for shafts of variable relative angular positionwhich comprises jaws secured to the coupling end of each shaft, each jawhaving a groove and a bore therein, a segment mounted on each of saidjaws and rotating in said groove, each segment having its innerperiphery, formed with a curved portion, a pivot for coupling saidsegments to one another, a guide member retaining said pivot constantlyon the bisector of the angle formed between the two shafts and slidingon said pivot, driving pins pivotally mounted in the bore of said jawsat right angles to said pivot, and engaging said guide member, meanscooperating with said driving pins for maintaining the joint assembledagainst axial tension, said driving pins having wide flat bearingsurfaces cooperating with wide flat bearing surfaces of said guidemembers, whereby the drive of one of the shafts by the other is effectedon the one hand by means of the two segments mounted on the pivot, andon the other hand by means of said flat bearing surfaces of the driving6 pins and of the guide member, said driving pins being mounted in thejoint such that each driving pin is tangential to the curved portion ofthe inner periphery of the corresponding segment which it thus retainsinits housing.

4. A homokinetic joint forshafts of variable relative angular position,which comprises a jaw secured to the coupling end of each shaft, each ofsaid jaws having a groove and a bore therein, a segment mounted on eachof said jaws and adapted to rotate in said groove, each segment havingits inner periphery formed with a curved portion, a pivot for couplingsaid segments to one another, a guide member adapted to retain saidpivot constantly on the bisector of the angle formed between the twoshafts and to slide on said pivot, and driving pins pivotally mounted ini the bore of each of said jaws, at right angles to said pivot, andadapted to engage said guide member, a pair of half caps forming acasing, said half caps cooperating with the driving pins to maintain thedevice assembled against axial tension, said driving pins having wideflat bearing surfaces adapted to cooperate with wide flat bearingsurfaces of said guide member, whereby the drive of one of the shafts'bythe other is effected, on the one hand by means of the two segmentsmounted on the pivot, and on the other hand by means of said flatbearing surfaces of the driving pins and of the guide member, saiddriving pins being mounted in the joint such that each driving pin istangential to the curved portion of the inner periphery of thecorresponding segment which it thus retains in its housing.

' GASTON LOUIS ARTHUR DEVOS.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS

